There have been many hundreds, if not thousands of devices and methods developed over the centuries for measuring distances. Planar and lines are distances conventionally measured by rulers, yard sticks and tape measures in two dimensions. The relatively recent development of the laser beam has revolutionized many industries and the use of the laser has also been used to focus and calculate certain lengths and levels. Laser levels have been used in construction for many years. They typically seek to produce a plane of light for a reference for construction projects. Laser levels have been used for large scale construction projects like commercial excavating, laying foundations, and installing drop ceilings. Laser levels save considerable time during initial layout of a construction job compared to other tools such as beam levels, chalk lines, or torpedo levels. Some examples of jobs where laser levels are useful include laying tile, mounting cabinets, installing counter tops, and building outdoor decks.
The alignment of surfaces is a perennial problem in a variety of fields, ranging from construction to interior decorating. Alignment is necessary for walls that should be perpendicular to a floor, or otherwise plumb. Masonry and brick-laying practitioners are well aware of the importance of plumbed and aligned surfaces and chalk lines. A home interior decorated with pictures and other wall ornamentation makes a much better appearance when the ornamentation is aligned, especially with respect to vertical or horizontal alignment. Many mechanical and electrical alignment devices are available, and some laser devices are available. However, some of these products are cumbersome, and others are not suitable for certain uses. Chalk lines, for instance, are sometimes undesirable for use in finished, interior areas.
In the construction industry, drawing an extension line from a reference line is usually done by applying a ruler or using an ink-string box. The reference line can be corner lines, fence lines, or any horizontal or vertical line defined by a square-beam leveler or other device. When applying a ruler to draw the extension line, one side of the ruler is used to be aligned with the reference line and the extension line can be formed by using a second ruler as an extension of the aforesaid ruler to elongate the reference line. Though this method can be accurate, this accuracy is only limited to short distances.
The ink-string box in the art comprises a box for carrying a roller at one half and ink at another half. The roller is pivoted on top of the box, and an extension string rolled around the roller. The extension string has a free end that is pulled over the ink and away from the box. While applying the ink-string box to draw an extension line of a reference line, the string is pulled out from the roller and mixed with the ink during the pulling operation, then aligned with the reference line, and then the extension line is formed by flipping the extended inked string to drop the ink lengthwise. Even though the ink-string box is suitable for use in medium or long distance applications, the operation of flipping the inked string is quite human-dependent and may need to be done in segments if a substantial length of string is to be pulled. Thus, a unique straight extension line may sometimes be difficult to achieve by applying the ink-string box and may be subject to human error.
Thus, there remains a need for a line-extension tool that provides accurate alignment and is effective for use in distances of all ranges, yet is easy to use and can be used quickly and efficiently. Because these laser levels can typically cost thousands of dollars, only those who regularly land larger construction projects can justify purchasing a laser level. Laser levels have not achieved widespread adoption by the general public despite the time savings because of their initial cost of ownership. The expense can be attributed to the cost of suitable laser sources such as He-Neon laser and associated optical system used to manipulate the beam generated by the laser source. Laser distance finders have advantages of being convenient for use, high accuracy, and short measuring time. Laser distance finders are widely used in a variety of applications, such as architecture, exploration and construction.
Leveling and/or plumbing devices are used in construction or other applications for marking or determining the level or plumb orientation of an object or surface. Many devices of this type utilize a laser generator that emits a beam of light, typically in a fan-type planar configuration, to provide the user with a visual representation of level or plumb on a surface. In order to fix the orientation of the device relative to the surface, which may be a floor or wall, it has been known to provide the device with extendable and retractable pins, which penetrate the surface and serve to temporarily secure the device to the surface.
While this type of temporary mounting arrangement functions satisfactorily to fix the position of the device relative to the surface, it is disadvantageous in that the pins leave holes in the surface that must be filled after use. In addition, this type of mounting arrangement does not allow slight alterations in the orientation of the device after engagement with the surface, in the event the device is not truly level or plumb when the pins are first inserted into the surface. Furthermore, this type of mounting arrangement can only be employed when the device is used on a surface that is capable of being penetrated by the pins. Accordingly, a temporary mounting arrangement of this type cannot be used on hard surfaces such as concrete, tile or the like.
A known laser distance finder usually comprises a laser generating device, a collimating lens positioned at an emitting end of the laser generating device for converting a laser beam generated from the laser generating device into a collimating measuring beam, a receiving lens disposed on one side of the laser generating device for receiving a reflected measuring beam from an object to be measured and focusing it into an image, an optoelectronic detector disposed in the distance finder for receiving the image of the reflected measuring beam and converting optical signals therein into corresponding electrical signals which is processed to obtain a distance measuring result.
U.S. Pat. No. 8,069,578 to Wright discloses a laser mounting tool to project a beam of light from a point aligned with a longitudinal edge of a first molding segment along the wall to locate and permit marking of the position of a corresponding second molding segment longitudinal edge. U.S. Pat. No. 6,195,902 to Jan et. al. teaches and claims a laser extender for accurately elongating a reference line. The laser extender includes a housing, a battery set, and a laser unit. The housing has an external basic flat plane for resting upon a flat surface and having a straight edge that is adapted to be aligned with a reference line, an internal accommodating space, and a plurality of holes for accessing the internal laser to the outside exterior of the housing. The battery set is provided inside the internal accommodating space. The laser unit, utilizing power provided by the battery set, is located inside the internal accommodating space for generating a spanning plane laser beam perpendicular to the basic flat plane of the housing and for extending the reference line defined by the straight edge. In addition, the laser extender can engage a beam leveler for enhancing the leveling ability of the laser extender.
U.S. Pat. No. 7,609,364 to Zhao et. al. discloses a laser distance finder comprising a laser generating device, a collimating lens positioned in a laser emitter end direction of the laser toward a desired distance to be measured. A generating device forward situated lens converts the laser beam generated from the laser into a collimating measuring beam while a receiving lens receives a reflected measuring beam from an object to be measured and focuses it into an image. An opto-electronic detector disposed in the distance finder receives the image of the reflected measuring beam and a reflective member is rotatably-mounted in an optical path of the collimating measuring beam via a rotating shaft. This is detector is capable of rotating to a blocking position and a non-blocking position around the rotating shaft. A transmission part located at one end of the reflective member has an interval apart from an axis of the rotating shaft. A worm having a plurality of teeth is connected to a motor. The transmission part engages with the teeth of the worm.